In xerography or an electrostatographic process, a uniform electrostatic charge is placed upon a photoreceptor surface. The charged surface is then exposed to a light image of an original to selectively dissipate the charge to form a latent electrostatic image of the original. The latent image is developed by depositing a liquid developer or finely divided and charged particles of toner upon the photoreceptor surface. The charged toner being electrostatically attached to the latent electrostatic image areas creates a visible replica of the original. The developed image is then usually transferred from the photoreceptor surface to a final support material such as paper and the toner image is fixed thereto to form a permanent record corresponding to the original.
In xerographic color copiers using a dry toner or liquid toner system, a photoreceptor surface is generally arranged to move in an endless path through the various processing stations of the color xerographic process. The color toner image is then transferred from the photoreceptor to a final support material such as paper and the surface of the photoreceptor is prepared to be used once again for the reproduction of a copy of a colored original. In this endless path, several stations, including color toner and development stations, are traversed. These stations generally involve one color toner dispensing unit in each development station. The present invention and embodiments are used in both dry ink systems and liquid printing systems.
In today's complex color systems (including printers and copiers), several potential problems need to be addressed and controlled. For example, space and apparatus size must be minimized including the size and life of color stations.
In current highlight color printer architecture, a color is unique to a customer-changeable unit or CCU (developer hardware). A customer requiring 10 colors would require 10 CCUs, 100 colors would require 100 CCUs and so on. As the number of available colors increases, then so does the number of CCUs. This becomes very expensive to the customer who wishes to print several colors or to the customers wishing to print a color only once.
If a customer today requires a different color in a color family, i.e. a darker orange rather than the orange color he or she presently has, the customer must purchase a new developer unit or CCU. Each unit costs several thousand dollars and changing color thereby can become costly and time consuming.
The present invention provides an easy procedure with a substantial savings to a customer wishing to change a color or colors in his color copier or printer.